Siliga, 6-2 and 325 pounds, is in his second season out of Utah. He had two assisted tackles against the Seahawks in the preseason game Saturday night at Seattle. Siliga already was at practice Wednesday.

“A true pro in the way he worked,’’ defensive coordinator Dan Quinn said of Siliga. “You could see his strength right away.”

Cherrington (6-3, 335) played college football at Richmond. Cherrington was not drafted, but signed with New England as a free agent before being released last week.

Both Siliga and Cherrington are longshots to make the 53-man roster, but the Seahawks coaches are trying to make sure they don’t come up short with the players on the defensive front.

Obviously, some of these men will be gone when cuts are made to get down to the 53-man roster (and eight possible practice squad players) before the regular season begins.

But a few of the newcomers have stood out, especially Mayowa and Schofield. Mayowa, a rush end from Idaho, has 2.5 sacks and four quarterback pressures in the first two preseason games.

Schofield, a fourth-year player from Wisconsin, has a sack, a forced fumble and a fumble recovery. Schofield knocked the ball out of quarterback Brock Osweiler’s hands and recovered it in the backfield in the Denver game last weekend.

“We started him at linebacker and then moved him back to Leo (rush defensive end),” Quinn said of Schofield, who played three seasons for the Arizona Cardinals. “He’s doing well.”

Hill, a third-round pick from Penn State, also has looked strong at defensive tackle. He’s in the running for the starting spot at the 3-technique defensive tackle, a spot vacated when Seattle lost Alan Branch to free agency in the offseason. Quinn said no decision had been made there, but McDaniel and Jaye Howard probably have the best chance of earning the first-team spot.

Avril and Bennent, two proven pass-rushers, and McDaniel, a defensive tackle in his eighth season, were the biggest off-season acquisitions on defense. Bennett has played both tackle and defensive end. Avril has yet to get in a game, and missed most of training camp with a hamstring injury. He also missed mini-camp and OTAs with a foot injury, but the Seahawks are counting on him to be a major contributor this season.

It was clear after the 2012 season that the Seattle coaches wanted to upgrade the defensive front and improve their rush. With defensive end Chris Clemons still recovering from off-season ACL surgery and defensive end/outside linebacker Bruce Irvin suspended for the first four games, the Seahawks are trying to ensure they have enough quality depth to make an improvement in that area.

No, there's no need for any kind of outright panic. The core, star-power pieces of the New York Giants' defensive line appear to be healthy. Defensive ends Justin Tuck, Jason Pierre-Paul and Osi Umenyiora, who form the engine of the league's most feared pass rush, are not the topic of this post. But the Giants announced Tuesday morning a number of other injuries that strike at the overall depth of their defensive line:

Shaun Rogers, the veteran defensive tackle who's been one of the surprise stars of training camp, is being treated for a blood clot in his leg. This is a very serious medical issue, and there's certainly no timetable at this point for Rogers' return.

Marvin Austin, the second-year defensive tackle who hasn't played an angry football game since 2009, is being treated for a back injury. Austin was suspended for his final season at North Carolina as part of that program's academic scandal and missed his rookie NFL season with an injury. The Giants have been hoping he could give their interior pass rush a boost, but they don't know to what (if any) extent they can count on him.

Defensive tackle Martin Parker, who missed the whole 2011 season with a foot injury, needs back surgery to repair a herniated disk.

Defensive end Justin Trattou continues to have heel and ankle problems, and the team says he's "not expected back on the field for several weeks." It seems as though Adrian Tracy, however, has been the leading candidate to replace Dave Tollefson as the reserve pass-rusher.

There is good news on defensive tackle Rocky Bernard, who has been practicing this week after missing Friday's preseason opener with a knee injury. But all in all, the Giants' depth on the defensive line -- particularly at defensive tackle -- is being challenged. Austin and Rogers were the two players the Giants were hoping could help make up for Canty's absence, and right now they don't know if they'll have either any time soon. Defensive tackle is an important position at which to be deep, since the physical demands of the position make it almost essential to rest and rotate players as much as possible.

If the issues continue, the Giants could be on the lookout for a defensive tackle as teams start to make cuts later this month. Meantime, some back-of-the-roster guys are going to get a whole lot of preseason snaps.